#include <stdio.h>
// 声明交换函数原型
void interchange(int u,int v);

int main(int argc, char *argv[]) {
	int x = 5, y = 10;
	printf("Originally x =%d and y = %d. \n", x, y);
	interchange(x,y);
	printf("Now x =%d and y = %d. \n", x, y);
	return 0;
}


// 定义函数
void interchange(int u,int v)
{
	int temp;
	printf("Originally u =%d and v = %d. \n", u, v);
	temp = u;
	u = v;
	v = temp;
	printf("Now u =%d and v = %d. \n", u, v);
}